1. Field of the Invention
The subject invention is directed to an on-line interconnect system for connecting a terminal with an internet and is specifically directed to the method and apparatus for enabling PC workstations on a local area network (LAN) to access the TCP/IP protocol internet without alteration of the PC hardware configuration and without the need for communication with a LAN server provider having a TCP/IP protocol stack.
2. Discussion of the Prior Art
An internet is a collection of disparate physical computer networks which are interconnected to function as a coordinated unit. The Internet is the interconnected network which includes the Defense Advanced Projects Research Agency (DARPA), the National Science Foundation (NSF), the Department of Energy (DOE) and the National Aeronautics and Space Administration (NASA), as well as most other research institutions, colleges and universities, and recently, most large companies. The Internet operates entirely under the protocol TCP/IP. Computers which communicate over the Internet must either use TCP/IP protocols or a TCP/IP protocol service provider.
Over the years local area networks or LANs have evolved and developed with protocols which are much simpler and more efficient than TCP/IP. The protocols do not require individual address management, or accessory functionality such as name servers to maintain the order of the membership. They were specifically designed to utilize a minimum memory capacity. While such systems are very useful for the intended purpose of linking a plurality of workstations to a central processor and to each other, they did not anticipate or plan for the need or desirability to permit each individual workstation to independently communicate via the Internet.
Several prior art systems have been developed with the objective of permitting LAN workstations to communicate with the Internet utilizing the required TCP/IP protocol. Initially, a second protocol, TCP/IP was added to each PC""s native LAN protocol or the LAN was converted to exclusive use of the TCP/IP protocol. IBM, Microsoft and Novell are examples of companies providing a second or conversion protocol. The difficulty with these solutions were the installation and management of TCP/IP stacks in the LAN PCs, more memory utilization for the protocol and a slowdown of normal LAN operation due to the inherent inefficiencies of TCP/Ip protocol when used as a LAN protocol.
These problems were reduced by introduction of a shared TCP/IP into an existing server, which eliminated the TCP/IP from the LAN workstations and permitted the LAN to operate in its native protocol. These solutions relied upon existing PC operating systems for the server, the TCP/IP for these systems housing the server and the LAN interface used by the server. Many such systems relied upon a special code or on start-up facilities to be installed in each LAN PC. Examples of such systems include Firefox and Internetware (for Novell NetWare servers), Ipswitch (OS/2) and Fel (Windows). All require a PC operating system to house the server and to provide access to the native LAN protocols. While such systems did eliminate the need to convert the LAN protocol and reduced the use of memory and the alteration of the LAN client PCs, each proved costly to install and maintain.
There have also been a number of recently issued patents which disclose systems for interconnection of various terminals across different networks by mapping or providing different protocol schemes, where the computers have different protocols or different communications architecture. For example, U.S. Pat. No. 5,353,283, issued to P. F. Tsuchiys, et al, on Oct. 4, 1994, discloses a method for use in a large communication internet with several interconnected networks having one or more interconnected nodes. Specifically, an algorithm is provided for writing a sequence of one or more identifiers suitable for use in indexing a forwarding table at each node in a special routing section of each packet to be transmitted via the internet, to provide a routing method adapted to achieve different routing criteria and styles to accommodate varying structures and architecture.
U.S. Pat. No. 5,355,365, issued to D. Bhat, et al, on Oct. 11, 1994, provides for a share modem resource to PCs connected through a LAN and to off network PCs.
Various other methods and apparatus have been developed to provide access to various internets from individual workstations of a LAN. However, to date, all of the systems available require at least a partial combination of expensive hardware additions to either the LAN in the form of a PC server or to each workstation of the LAN; substantial memory utilization; use of a protocol service provider and/or limited simultaneous access to the internet via the shared system, for example, one user at a time on a shared modem.
It is, therefore, desirable to provide an internet access system wherein each LAN workstation can simultaneously directly communicate with the internet without requiring substantial hardware modification or DOS memory utilization in existing LAN workstations or servers.
The subject invention is directed to a method and apparatus for connecting a plurality of LAN workstations to the internet via an on-line server/interface that does not require a PC operating system dedicated to the server. In the preferred embodiment the server operates in TCP/IP protocol for communication over the Internet. Unlike prior art systems, the subject invention utilizes only a single connection to the internet in order to permit the entire LAN to operate simultaneously on the Internet. Specifically, only a single phone line is required to simultaneously serve all LAN workstations. The method and apparatus of the subject invention is equally well suited to connect via a telephone line connection to an Internet providers""s SLIP or PPP or via an Ethernet connection to a router or direct connection by any available means.
The method and apparatus of the subject invention is a unique construction, not relying on a PC operating system, but is a dedicated system specifically designed for connecting a LAN to the internet without disturbing the native LAN protocol, while communicating via the internet protocol such as, by way of example, TCP/IP. The resulting system supplies a very high performance protocol facility equal to or exceeding that of the dedicated stacks provided for individual PCs at a fraction of the cost. The LAN is provided with a complete internet protocol service, supporting functions not generally available in the dedicated stacks previously provided for individual PCs. In the preferred embodiment the system provides a TCP/IP service to the LAN with support for broad compatibility with all WINSOCK applications which previously were run on dedicated PC stacks.
The subject invention provides full internet connection without any alteration of the LAN hardware and with minimum memory utilization. The configuration of the preferred embodiment does not require PC operating system support and does not rely on the existing LAN processors to be used as TCP/IP protocol servers. A significant feature of the invention is the simplicity of installation and the minimization of management requirements once installed. Basically, a xe2x80x9cblack boxxe2x80x9d is connected, on-line, to the LAN data line, and connected to a standard telephonic line system in order to connect each LAN workstation, individually, to the internet. Simultaneous use of the internet by each of the LAN workstations is supported by the integrated server of the present invention.
By way of comparison, the internet access system of the subject invention works in the manner of a multi-plex switching network for multiple telephone stations, wherein each telephone station has direct access to outside lines through a central unit, but may bypass the central unit entirely when communicating within the network. The subject invention does not interfere with the internal LAN communications, but provides access directly to the internet using the internet protocol.
The system of the subject invention is a xe2x80x9cfrom-the-ground-upxe2x80x9d unique approach to providing LAN communications with the internet. The architecture of the preferred embodiment eliminates the need for support from existing operating systems with its TCP/IP stack, such as, by way of example, Windows, Windows95, NT, OS/2, UNIX or NetWare server NLM. Each of these operating systems require substantial memory, supporting hard disk drives, and often supporting peripherals. They also provide inadequate support from their TCP/IP stacks resulting in slow performance, and often instability and incomplete functionality.
It is, therefore, an object and feature of the subject invention to provide a system for connecting LANs to the internet without requiring a PC operating system, wherein all of the LAN workstations can communicate with the internet via a single telephone line or other single point of network access.
It is another object and feature of the subject invention to provide a system wherein the LAN continues to operate in its native protocol, without modification, while having the capability of communicating with the internet utilizing the internet protocol.
It is yet another object and feature of the subject invention to provide a system supplying a high performance TCP/IP facility equal to or exceeding that of dedicated TCP/IP stacks without requiring or using PC operating support.
It is an additional object and feature of the subject invention to provide a simple, easy-to-use box to bring internet services to every PC workstation on a LAN without interfering in any manner with the operation of the LAN.
Other objects and features of the invention will be readily apparent from the drawings and detailed description of the preferred embodiment.